In general, an electrographic printer forms an image on a sheet by a charging process, an exposure process, a development process, a transfer process and a fusion process. In the charging process, a photo-conductive insulation layer is uniformly charged. In the exposure process, an electrostatic latent image is formed by exposing the photo-conductive insulation layer and by eliminating charges on the exposed parts. In the development process, the electrostatic latent image is visualized by adhering toner containing colorant to the photo-conductive insulation layer. In the transfer process, a toner image, which is the obtained visualized image, is transferred from the photo-conductive insulation layer onto the sheet. In the fusion process, the toner image is fixed onto the sheet by heating, pressing or through other known fusion methods. A developing device that performs the development process includes a development roller and a supply roller that supplies toner to the development roller.
In a conventional toner cartridge that supplies toner to the developing device, an agitation member is provided inside a cylindrical shutter part that opens and closes a lower ejection opening formed on a cylindrical part of an external cylinder member. The whole agitation member is rotated while the center of a shaft part of the agitation member over the cylindrical part is changed in order to reduce the remaining amount of the toner that remains unused in the toner cartridge (e.g., see Japanese Laid-Open Patent Application No. 2009-175309 (especially, paragraphs 0027-0029 and 0048, and FIGS. 9 and 13)).
However with a conventional toner cartridge, if the agitation member is removed, it is relatively difficult to smoothly supply toner from the toner cartridge to the developing device.
At least one objective of the embodiment disclosed and claimed in the present application, therefore, is to smoothly supply developer from a developer container (e.g., toner cartridge) to a developing device.